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To better understand the characteristic properties of violacein biosynthesized by engineered Escherichia coli VioABCDE‐SD, a convenient and simplified method was designed to extract violacein and its stability, antimicrobial activity, and antioxidant capacity were analyzed. Different from the traditional extraction methods, our new method is easier and less time consuming and can directly obtain violacein dry powder product with a higher extraction rate. Low temperature, dark condition, neutral pH, reducing agents, Ba2+, Mn2+, Ni2+, Co2+, and some food additives of sucrose, xylose, and glucose were conducive to maintaining its stability. The violacein also exhibited surprisingly high bacteriostatic action against Gram‐positive Bacillus subtilis, Deinococcus radiodurans R1, and Staphylococcus aureus and Gram‐negative Pseudomonas aeruginosa, but no effect on E. coli. The violacein of VioABCDE‐SD exhibited strong antioxidant activity, with the scavenging rate of 1,1‐diphenyl‐2‐picrylhydrazyl free radicals reaching 60.33%, the scavenging efficiency of hydroxyl radical scavenging reaching 56.34%, and the total antioxidant capacity reaching 0.63 U/mL. Violacein from VioABCDE‐SD can be synthesized directionally with better stability, antibacterial, and antioxidant properties compared with that from the original strain Janthinobacterium sp. B9‐8. Therefore, our study indicated that violacein from engineered E. coli VioABCDE‐SD was a kind of new antibiotic with potential biological activities, which may have potential utility in multiple areas such as pharmacological, cosmetics, and healthy food industries.

To investigate the properties of carotenoids from the extremophile Deinococcus xibeiensis R13, the factors affecting the stability of carotenoids extracted from D. xibeiensis R13, including temperature, illumination, pH, redox chemicals, metal ions, and food additives, were investigated. The results showed that low temperature, neutral pH, reducing agents, Mn 2+ , and food additives (xylose and glucose) can effectively improve the stability of Deinococcus carotenoids. The carotenoids of D. xibeiensis R13 exhibited strong antioxidant activity, with the scavenging rate of hydroxyl radicals reaching 71.64%, which was higher than the scavenging efficiency for 1,1-diphenyl-2-picrylhydrazyl free radicals and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) free radicals (44.55 and 27.65%, respectively). In addition, the total antioxidant capacity reached 0.60 U/ml, which was 2.61-fold that of carotenoids from the model strain Deinococcus radiodurans R1. Finally, we predicted the gene clusters encoding carotenoid biosynthesis pathways in the genome of R13 and identified putative homologous genes. The key enzyme genes (crtE, crtB, crtI, crtLm, cruF, crtD, and crtO) in carotenoid synthesis of D. xibeiensis R13 were cloned to construct the multigene coexpression plasmids pET-EBI and pRSF-LmFDO. The carotenoid biosynthesis pathway was heterologously introduced into engineered Escherichia coli EBILmFDO, which exhibited a higher yield (7.14 mg/L) than the original strain. These analysis results can help us to better understand the metabolic synthesis of carotenoids in extremophiles.

52Colorectal cancer (CRC) is one of the most common cancers in China. In 2003, a systematic CRC 53 registry that enables the determination of CRC incidence and mortality and a CRC screening project 54 were introduced in the Jing'an district of Shanghai by the municipal government. This study assessed 55 the registry data to determine the status of CRC and CRC screening rates in the core district of an 56 urban area of China. Data were retrieved from the Official registry information systems of Jing'an 57 district Shanghai Cance. The incidence and mortality of CRC, as well as population-based CRC 58 screening rates, were analysed. Individuals who screened positive for CRC based upon results of a 59 high-risk factor questionnaire (HRFQ) and a faecal immunochemical test (FIT) were selected for 60 follow-up colonoscopy (CSPY). From the registry data collected between 2003 and 2013, the 61 standardized incidence rate was 26.44/10 5 , with a significant gender difference. The CRC 62 standardized mortality rate was 10.08/10 5 . In 2013, 17,866 individuals (21.6%) enrolled for CRC 63 screening among the 82,602 candidate residents. The positive screening rate was 16.28% 64(2909/17866). Among the 2909 positives, 508 (17.5%) underwent follow-up CSPY. In 41.3% of 65 these individuals (210/508), abnormal lesions were detected. Of these, 8 (1.57%) lesions were 66 diagnosed as CRC, and 142 (28.0%) were identified as precancerous lesions. During the assessment 67 period, both the incidence and mortality of CRC in the Jing'an district were determined in the area of 68 high CRC prevalence in Chin. Nevertheless, the rate of participation in CRC screening was low 69 (21.6%), and the rate of participation in follow-up CSPY for individuals who screened positive was 70 only 17.5%. Improved participation in CRC screening and follow-up CSPY is expected to lower the 71 incidence and mortality of CRC significantly in the rural areas of China. (288) 72 73 74 75 76 77 78 79 80 4 81 82 131 CDC (Shanghai Jingan Center for Disease Control and Prevention), through the Shanghai Cancer 132 Registry Information System and the Shanghai All Causes of Death Registration Reporting System 133 organized by the Shanghai Government and Jingan municipal office. 134 135 The CRC screening was conducted by six sites of the community health service center in this district 136 under supervise by the health bureau of the Shanghai Government and Jingan municipal office. 137 Colonoscopy and the follow-up diagnosis for further treatment under supervise by the health bureau 138 were performed in the four designated hospitals (Jing'an District Central hospital, Huashan hospital, 139 Huadong hospital and Post & Telecommunications Hospital of Shanghai.).140 307 assessment and development of other assessments are in progress[24-29], the FIT used in this study 308 appears reliable and appropriate for CRC screening at this stage.309 310 Follow-up colonoscopy (CSPY) is indispensable for reducing CRC mortality in individuals who 311 screen positive for CRC 312 CSPY is c...